<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .focus {
            width: 750px;
            height: 150px;
            background-color: cadetblue;
            margin: 100 auto;
        }
    </style>
</head>

<body>
    <div class="focus">
        <img src="upload/1.png" alt="故宫">
        <img src="upload/2.png" alt="山水">
        <img src="upload/3.png" alt="清明上河图">
    </div>
    <script>
        /*
            使用步骤:
                1. 登录官网，查看效果和使用说明。
                2. 下载
                3. 引入 CSS H5 JS
                4. 调试 CSS H5 JS
        */
       
    </script>
</body>

</html>